Aquacultural Engineering最新文献

{"title":"Hydrodynamic performance and pollutant removal efficiency in a dual-channel RAS with wastewater suction pipes","authors":"Jun Zhang,&nbsp;Jun Guo,&nbsp;Yujun Zhang,&nbsp;Hongjin Zhang,&nbsp;Shouqi Cao,&nbsp;Qingsong Hu","doi":"10.1016/j.aquaeng.2026.102688","DOIUrl":"10.1016/j.aquaeng.2026.102688","url":null,"abstract":"<div><div>To enhance the pollutant removal efficiency in the Recirculating Aquaculture System (RAS), a sewage suction pipe is typically installed in the Recirculating Aquaculture Tank (RAT), connecting the underflow port and tank wall. Its primary function is to remove particulate pollutants accumulated at the tank bottom, such as feces and uneaten feed. In this study, an octagon-shaped dual-channel RAT in actual operation was used as the research object. A multiphase flow numerical model was established based on the two-phase flow theory, and the accuracy of this model was validated through physical scale-model experiments. Key hydrodynamic parameters, including flow velocity, vorticity, and water mixing uniformity, were systematically investigated. Meanwhile, the pollutant discharge rates at the underflow port and suction pipe outlet were quantitatively analyzed to evaluate the system’s pollutant removal efficiency. The results showed that the sewage suction pipe significantly affects the rotational flow field and vortex structure inside the RAT: As the angle of the suction pipe increases, the velocity gradient near its water inlet decreases, which weakens the tendency of particulate matter to aggregate toward the RAT center and thus hinders particulate discharge. Additionally, the diameter of the suction pipe exerts a notable impact on the flow velocity in the RAT: When the pipe diameter increases, the overall flow velocity and momentum transfer efficiency in the RAT decrease, the water flow uniformity index reduces, and the particulate discharge rate presents a trend of \"first increasing and then decreasing\".</div></div>","PeriodicalId":8120,"journal":{"name":"Aquacultural Engineering","volume":"113 ","pages":"Article 102688"},"PeriodicalIF":4.3,"publicationDate":"2026-03-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145973046","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Modelling the effects of temperature and chlorophyll on growth and survival of the oyster Crassostrea gigas in two different cultivation systems","authors":"D.C. Galhanas ,&nbsp;A.M.T. Mata ,&nbsp;M. Simões ,&nbsp;M.M. Silva ,&nbsp;R. Salgado","doi":"10.1016/j.aquaeng.2026.102696","DOIUrl":"10.1016/j.aquaeng.2026.102696","url":null,"abstract":"<div><div>With rising global demand for oysters, optimizing aquaculture systems to maximize productivity while ensuring sustainability has become increasingly critical. This study evaluates two cultivation methods rectangular bags and cylindrical baskets, for Pacific oyster <em>Crassostrea gigas</em> over a 12-month period in Sado estuary (Portugal). Oyster growth (using four initial weights: 5, 10, 20, and 45 g), survival rates, and water quality parameters, (pH, dissolved oxygen, salinity, temperature <em>in situ</em> and chlorophyll-a, phosphate and total nitrogen concentrations), were monitored. Mathematical models were developed to quantify growth dynamics under varying environmental conditions. Overall results, averaged across the four independent experiments, showed that cylindrical baskets significantly outperformed rectangular bags, exhibiting a higher growth rate (0.39 g d⁻¹) and higher survival (35 %) compared with bags (0.26 g d⁻¹ and 30 %, respectively). Temperature and chlorophyll-a concentration was identified as primary growth-limiting factors, with oyster biomass accumulation positively correlated to chlorophyll-a availability and negatively affected by low temperatures extremes (&lt;10°C). The derived models integrate these environmental drivers, allowing accurate predictions of oyster growth under seasonal variability. Although differences in growth performance were observed between cultivation methods, both systems allowed oysters to reach full commercial size (30–60 g) within a maximum of eight months in Sado estuary. For 5 g seed oysters cultivated from July on, triploid <em>C. gigas</em> required approximately 7–8 months in rectangular bags and 5–6 months in cylindrical baskets to attain market size. Overall, the results highlight the superior performance of cylindrical basket systems for commercial oyster farming and demonstrate the usefulness of mathematical models as robust tools for production planning and yield optimization under variable environmental conditions.</div></div>","PeriodicalId":8120,"journal":{"name":"Aquacultural Engineering","volume":"113 ","pages":"Article 102696"},"PeriodicalIF":4.3,"publicationDate":"2026-03-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146034258","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Operational agricultural water management in river-based aquaculture: A machine-learning approach to predict dissolved oxygen in the Halda River, Bangladesh","authors":"Md. Abdullah Al Mamun Hridoy ,&nbsp;Paolo Pastorino ,&nbsp;Chiara Bordin ,&nbsp;Matteo Bodini ,&nbsp;Nayan Dhar ,&nbsp;Petra Schneider ,&nbsp;Leonardo Goliatt ,&nbsp;Pakorn Ditthakit ,&nbsp;Bruno da Silva Macêdo ,&nbsp;Khairul Nizam Abdul Maulud","doi":"10.1016/j.aquaeng.2026.102693","DOIUrl":"10.1016/j.aquaeng.2026.102693","url":null,"abstract":"<div><div>Dissolved Oxygen (DO) represents a key operational constraint for river-dependent aquaculture, and short-term DO forecasting can support practical agricultural water management in systems that directly abstract river water. Relying on daily physicochemical observations from the Halda River, Bangladesh (April 2024–March 2025), four Machine Learning (ML) models were evaluated for DO prediction, <em>i.e.</em> Linear Regression, Artificial Neural Network, Support Vector Machine, and Random Forest. Among the latter ML models, Random Forest achieved the highest predictive performance (R² = 0.9015, RMSE = 0.0833, and MAE = 0.0574), substantially outperforming the considered baseline Linear Regression model (R² = 0.4469, RMSE = 0.1892, and MAE = 0.1478). DO was generally stable (about 6.3–7.0 mg/L) while ionic variables, e.g., chloride, conductivity, and Total Dissolved Solids (TDS), showed pronounced dry-season peaks, thus indicating conditions where oxygen stress can become more likely and less predictable. Explainable ML interpretation developed on feature importance and SHapley Additive exPlanations (SHAP) consistently identified water temperature and ionic concentration proxies, especially chloride, alongside conductivity, and TDS, as the dominant drivers of DO variability. Relying on the latter findings, an operational decision-support workflow is proposed in which forecasts based on the Random Forest ML model are paired with low-cost monitoring of temperature and chloride to trigger time-graded farm actions, such as targeted aeration, temporary intake closure, and stocking/feeding adjustments. The reported results in the developed study demonstrate a transferable pathway for moving from accurate and interpretable ML forecasts to actionable agricultural water management protocols that reduce risk of critical losses in river-based aquaculture.</div></div>","PeriodicalId":8120,"journal":{"name":"Aquacultural Engineering","volume":"113 ","pages":"Article 102693"},"PeriodicalIF":4.3,"publicationDate":"2026-03-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146034259","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Integrating multi-clusters classification with temporal structure of pulse improves feed consumption prediction across Penaeus vannamei size groups","authors":"Boshan Zhu ,&nbsp;Yesen Li ,&nbsp;Xiaoye Han ,&nbsp;Dapeng Liu ,&nbsp;Fang Wang ,&nbsp;Chao Yang","doi":"10.1016/j.aquaeng.2026.102697","DOIUrl":"10.1016/j.aquaeng.2026.102697","url":null,"abstract":"<div><div>Passive acoustic monitoring (PAM) is increasingly used in precision feeding systems for Pacific white shrimp (<em>Penaeus vannamei</em>). However, predictive accuracy is constrained because feeding behavior is not the sole source of acoustic pulses. Here, we combine a Gaussian mixture hidden Markov model (GMM–HMM) with recurrence quantification analysis (RQA) to characterize feeding-related pulse features and temporal structure across four size classes (1, 3, 7, and 12 g). Nine acoustically distinct pulse clusters were classified, and an optimal multi-cluster metric was constructed for each size. Across sizes, the multi-cluster metric outperformed both single-cluster and total pulse counts, reducing prediction error and increasing interpretability. Predictive error decreased by 14.4 %, 14.3 %, and 24.6 % in the 1 g, 3 g, and 7 g groups, respectively. In the 12 g size group, total pulses were not significantly related to feed consumption, whereas the optimal multi-cluster metric remained predictive, and the error was reduced by 6.5 %. With the growth of shrimp, pulse signals shifted from more singular and stable to more diverse and diffuse, weakening the pulse–consumption associations. Nonetheless, high-frequency, and short-duration clusters exhibited a consistent positive association with feed consumption across all size classes and should be prioritized as robust indicators of true feeding behavior in culture monitoring. RQA further showed clear, stable feeding and post-feeding phases in smaller shrimp, which supports regularized feeding. Larger shrimp, however, displayed sparse, irregular sequences with blurred phase transitions, indicating a need for higher feeding frequency and an extended feeding stage. In summary, this study is the first to delineate the characteristics of different pulse clusters and the temporal structure of pulses across size classes in <em>P. vannamei</em>, improving PAM interpretability and feed consumption monitoring accuracy, and providing a scientific basis for optimizing the size-specific feeding strategies and advancing precision feeding technology.</div></div>","PeriodicalId":8120,"journal":{"name":"Aquacultural Engineering","volume":"113 ","pages":"Article 102697"},"PeriodicalIF":4.3,"publicationDate":"2026-03-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146184881","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Analysis of drag force, deformation and stress distribution of biofouled flexible nets","authors":"Songchen Yu ,&nbsp;Ning Wang ,&nbsp;Hongde Qin ,&nbsp;Peng Li","doi":"10.1016/j.aquaeng.2026.102698","DOIUrl":"10.1016/j.aquaeng.2026.102698","url":null,"abstract":"<div><div>This research integrates laboratory experiments and numerical simulations to examine hydrodynamic behavior and structural responses of clean and biofouled flexible nylon nets under varying current velocities and attack angles. Experiments were conducted in a recirculating water channel, while fluid-structure interaction simulations coupled a large-deformation nonlinear structural model with large-eddy simulation. Results indicate that biofouling elevates drag forces by 35.5–41.4 % across tested velocities ranging from 0.3 m/s to 0.8 m/s. In addition, biofouling fundamentally alters deformation and stress patterns, increasing peak equivalent stresses and intensifying local stress concentrations at knots and attachment points. It follows that the stress distribution becomes more heterogeneous, thus increasing the risk of twine failure. Furthermore, net solidity, aperture size and twine diameter critically influence hydrodynamic loading and have been analyzed and assesed.</div></div>","PeriodicalId":8120,"journal":{"name":"Aquacultural Engineering","volume":"113 ","pages":"Article 102698"},"PeriodicalIF":4.3,"publicationDate":"2026-03-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146185014","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Pixel-level quantification of biofouling taxa associated with salmon aquaculture infrastructure using deep learning","authors":"R. Cappaert ,&nbsp;W. Yang ,&nbsp;D.J. Ross ,&nbsp;C. Johnston ,&nbsp;C. MacLeod ,&nbsp;C.A. White","doi":"10.1016/j.aquaeng.2025.102682","DOIUrl":"10.1016/j.aquaeng.2025.102682","url":null,"abstract":"<div><div>Biofouling communities readily develop on infrastructure used in marine-based salmon. Knowing the composition of biofouling assemblages at specific locations provides valuable information to aid decision-making on what management practices should be prioritized. Analyzing large quantities of <em>in situ</em> footage of nets or processing taxonomic samples is time-consuming and a practical bottleneck for industry. This work developed deep learning methodologies to automatically segment batches of <em>in situ</em> images and visualize the relative abundance of important biofoulers, with the objective of providing industry with rapid-assessment tools to quantify the structure of <em>in situ</em> biofouling communities. The main tool developed in this paper, an Ensemble Soft Voting System that segments twelve biofouling classes along with water and unfouled netting, obtained a global accuracy of 86.7 % and a mean accuracy of 67.7 % across the test dataset. Consistent misclassification of stalked <em>Pyura</em> species as unstalked solitary ascidians and clumps of bryozoans as sponges led to discrepancy between global and mean accuracy. The “matrix” class considered by the Ensemble Soft Voting System was then further divided into two subclasses that pose different risks to farmed salmon depending on the abundance of hydrozoan taxa, using a single Convolutional Neural Network with a global accuracy of 81.8 % and a mean accuracy of 84.1 % across the test dataset. These tools provide industry with accurate, rapid data on the relative abundance of biofouling taxa relevant for fish health outcomes and allow industry to make operational decisions in near real-time with minimal manual input and disruption to operations.</div></div>","PeriodicalId":8120,"journal":{"name":"Aquacultural Engineering","volume":"113 ","pages":"Article 102682"},"PeriodicalIF":4.3,"publicationDate":"2026-03-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145836840","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Design and performance verification of crab seedling automatic counting equipment based on improved YOLOv11+DeepSORT","authors":"Changfeng Tian ,&nbsp;Xuan Che ,&nbsp;Lei Ge ,&nbsp;Zhi Qu ,&nbsp;Mengxia Han","doi":"10.1016/j.aquaeng.2025.102680","DOIUrl":"10.1016/j.aquaeng.2025.102680","url":null,"abstract":"<div><div>In the current crab seedling aquaculture industry, the traditional weighing method for counting suffers from large errors and fails to meet the requirements of precise aquaculture density regulation. To address this issue, this study designed an equipment system comprising a segmented buffer slideway, an industrial camera, an image processor, and an LED diffused light source. Meanwhile, a crab seedling detection, recognition, and dynamic tracking algorithm based on improved YOLOv11 combined with DeepSORT was proposed to realize automated counting of crab seedlings. The results showed that the improved YOLOv11 model outperformed the original YOLOv11: its precision (P) increased by 1.0 %, recall (R) increased by 0.3 %, mAP50 reached 98.8 %, and mAP50–95 increased by 1.5 %. Additionally, the preprocessing time decreased from 3.1 to 2.6 ms, and the FLOPs increased from 3.1 to 3.2. The improved model also avoided the ID switch and missed detection issues of the original model. By quantifying the differences between target boxes and introducing a distance measurement factor, the problem of ID update after complete occlusion of crab seedlings in frame 78 was solved, ensuring stable IDs when occluded crab seedlings were re-detected. Furthermore, to verify the feasibility of the equipment, crab seedlings of three specifications were used for experiments. The results indicated that the average counting precision (ACP) of the equipment was 19.3, 16.6, and 12.3 % higher than that of the traditional weighing method for the three specifications, respectively, with a counting error rate≤ 1 %. The equipment could also distinguish active individuals from residual limbs and impurities. In terms of protection, the cumulative damage rate of the equipment was 10, 5, and 3 % lower than that of the weighing method for the three specifications, respectively, and the damage rate of crab seedlings with a specification of 10–15 g and above was reduced to 0. This equipment breaks the dependence of the weighing method on the uniformity of individuals, can meet the needs of precise counting in scenarios such as crab seedling density monitoring and transaction settlement, and provides equipment support for the intelligent management of the crab seedling industry.</div></div>","PeriodicalId":8120,"journal":{"name":"Aquacultural Engineering","volume":"113 ","pages":"Article 102680"},"PeriodicalIF":4.3,"publicationDate":"2026-03-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145836839","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Technological approaches to enhance water efficiency in aquaculture: Aiming towards sustainable intensification","authors":"Danielle de Bem Luiz ,&nbsp;Hellen de Almeida Kato ,&nbsp;Mariana Schneider ,&nbsp;Viviane Rodrigues Verdolin dos Santos ,&nbsp;Regina de Fátima Peralta Muniz Moreira","doi":"10.1016/j.aquaeng.2025.102679","DOIUrl":"10.1016/j.aquaeng.2025.102679","url":null,"abstract":"<div><div>Sustainable aquaculture requires innovative water management systems that balance environmental conservation with product quality. This review explores advanced technologies such as photocatalysis, ozonation, integrated multitrophic aquaculture, and probiotics as strategies to diminish nutrient discharge, reduce off-flavor accumulation, and improve fish health. In addition to enhancing production efficiency, these solutions facilitate climate adaptability, decrease freshwater use, and promote circular economy strategies within aquatic food systems. The combination of these technologies may enhance water reuse, reduce organic contaminants such as antibiotics and geosmin, and optimize system resilience to climatic stressors. Nonetheless, numerous of these methodologies face limitations related to costs, scalability, and relevance in resource-limited environments. Although promising results, additional investigation is required to overcome these obstacles and enhance these systems for extensive deployment, guaranteeing likelihood of economic feasibility and long-term ecological equilibrium.</div></div>","PeriodicalId":8120,"journal":{"name":"Aquacultural Engineering","volume":"113 ","pages":"Article 102679"},"PeriodicalIF":4.3,"publicationDate":"2026-03-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145797660","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Pilot outdoor cultivation of a marine haptophyte Tisochrysis lutea using a novel floating photobioreactor driven by electric rotary motor","authors":"Masashi Fujii ,&nbsp;Yoshiki Takayama ,&nbsp;Chiaki Tomatsu ,&nbsp;Kashu Sano ,&nbsp;Hidemi Kishinami ,&nbsp;Minamo Hirahara ,&nbsp;Abd Wahab Farahin ,&nbsp;Razif Harun ,&nbsp;Fatimah Md. Yusoff ,&nbsp;Fadhil Syukri ,&nbsp;Ken Furuya ,&nbsp;Tatsuki Toda","doi":"10.1016/j.aquaeng.2025.102666","DOIUrl":"10.1016/j.aquaeng.2025.102666","url":null,"abstract":"<div><div>Floating photobioreactors have recently attracted attention to utilize water surface areas such as estuaries, oceans, lakes, aquaculture ponds for microalgae biomass production. Outdoor cultivations of <em>Tisochrysis lutea</em> with a novel floating oscillation photobioreactor, named CRADLE, were conducted in triplicates under tropical climatic setting in Malaysia. The batch cultivations were performed in September 2022, November 2023, and March 2023. Biomass and fucoxanthin were analyzed using culture aliquot sampled every morning. The maximum dry weights of <em>T. lutea</em> were 0.99 ± 0.11–1.1 ± 0.0 g L⁻¹ under continuous mixing in November 2022 and March 2023. The dry weight and fucoxanthin yield under continuous mixing were significantly higher than that achieved under intermittent mixing (<em>p</em> &lt; 0.05). Additionally, the November 2022 and March 2023 experiments showed higher maximum dry weight than that in September 2022 due to the supplementation of 0.01 M NaHCO₃. Considering the energy cost of mixing, the CRADLE demonstrated a 65.9–71.1 % reduction in mixing energy compared with aerated cultivation with bubble column photobioreactor and obtained fucoxanthin productivity per unit of mixing energy within the range of 1.2 ± 0.08–3.6 ± 0.48 mg kWh⁻¹ under continuous oscillation mixing. Overall, these results contribute to the understanding of how oscillation mixing affects microalgae production and fucoxanthin accumulation. The CRADLE, which uses the electric rotary motor for culture mixing, reduced mixing cost and did not require temperature control, thereby demonstrating its potential for energy-saving microalgal cultivation.</div></div>","PeriodicalId":8120,"journal":{"name":"Aquacultural Engineering","volume":"113 ","pages":"Article 102666"},"PeriodicalIF":4.3,"publicationDate":"2026-03-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145692423","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Performance characterization of a diffused aeration basin for carbon dioxide removal in RAS","authors":"Laura Bailey ,&nbsp;Brian Vinci","doi":"10.1016/j.aquaeng.2025.102678","DOIUrl":"10.1016/j.aquaeng.2025.102678","url":null,"abstract":"<div><div>Fish produce dissolved carbon dioxide (CO₂) as a normal outcome of aerobic metabolism and transfer this gas through their gills into the surrounding water. Dissolved carbon dioxide control unit processes are necessary to maintain safe levels of CO₂ in the culture tanks of recirculating aquaculture systems (RAS) with high stocking densities. The project's goal was to evaluate the removal of CO₂ using low-head technology and to identify design criteria for optimizing such technologies. The study examined an aeration basin that used diffused air as the stripping gas in a shallow water column. Diffused aeration basins are often used in current RAS designs after a moving bed biofilter. This research evaluated hydraulic loading rates (204, 306, 407, 611, 815, and 1182 L min⁻¹ m⁻² (5, 7.5, 10, 15, 20, and 29 gal min⁻¹ ft⁻²)), three influent CO₂ levels (10, 15, and 25 mg L⁻¹), two diffused airflow rates (G:L ratio of 2 and 5), and two basin depths (0.97 and 0.48 m (38 and 19 in)) to assess CO₂ removal efficiencies in a research-scale aeration basin. Results showed that aeration basins designed with hydraulic loadings of 407–815 L min⁻¹ m⁻² (10–20 gal min⁻¹ ft⁻²) and a G:L ratio of 5 achieved 50–60 % CO₂ removal but decreased to 30–35 % as hydraulic loading reached 1182 L min⁻¹ m⁻² (29 gal min⁻¹ ft⁻²). Basins with hydraulic loadings of 407–815 L min⁻¹ m⁻² (10–20 gal min⁻¹ ft⁻²) and a G:L ratio of 2 achieved 40–50 % CO₂ removal, but removals fell to 20–30 % at a hydraulic loading of 1182 L min⁻¹ m⁻² (29 gal min⁻¹ ft⁻²). These removal efficiencies suggest that aeration basins can be designed to control CO₂ over the typical range of concentrations found in RAS.</div></div>","PeriodicalId":8120,"journal":{"name":"Aquacultural Engineering","volume":"113 ","pages":"Article 102678"},"PeriodicalIF":4.3,"publicationDate":"2026-03-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145748925","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}